While small-unit leaders have obvious duties of critical importance in actual combat operations, any professional, experienced combat leader will tell you that gunfights are not won on the battlefield. Gunfights, logistics considerations aside, are won on the training field ("The more you sweat in training, the less you bleed in combat."). The single, most absolutely critical skills task of any effective tactical leader is the development, validation, and guidance of realistic, relevant training of all subordinate elements.
The first elemental building block of tactical training is the individual. The individual operator must master the safe use of his weapon in order to be able to train with a team element (everyone wants to do cool-guy, high-speed shooting shit, and it's relatively easy to get good enough quickly on a square range. Shit gets a lot more complicated though, when everyone is moving in different directions, at high speed, gunfire is raging all around, and the stress-induced tachycardia starts kicking in...). The shooter who cannot learn to maintain muzzle awareness AND situational awareness at the same time isn't ready to work on team drills live-fire.
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